IPCC第一工作组评估报告分析及建议

2021年8月6日,政府间气候变化专门委员会(IPCC)第一工作组第六次评估报告(AR6)发布,针对气候系统变化科学领域最新研究进展和成果进行了全面、系统的评估. AR6以更强有力的证据进一步确定了近百年全球气候变暖的客观事实,人类活动对气候变暖影响的信号更为清晰. 本文总结了历次IPCC评估报告,并从气候现状、未来可能的气候状态、风险评估和区域适应气候变化信息以及减缓未来气候变化4个方面对AR6进行系统梳理. 结果表明:人类活动产生的温室气体对大气、海洋、冰冻圈和生物圈的影响前所未有,引发了全球许多地区的极端天气和气候极端事件. 未来若温室气体排放没有显著减少,到2100年全球地表温度将至少升高2.1 ℃;如若人类影响得到有效改善,在最低排放情景(SSP1-1.9)中,2055年将变为负碳,到21世纪末气温开始再次下降. 减少CH₄等其他污染物可以为全球气候治理争取时间,并改善空气质量. 建议中国应对气候变化应加强基础科学研究,聚焦模式开发和应用及与各工作组之间的衔接,加快短寿命气候强迫(SLCFs)与温室气体协同控制研究,强化应对气候变化政策措施的科技支撑等.      

Learning about climate change solutions in the IPCC and beyond

There has been much debate about the assessment process of the Intergovernmental Panel on Climate Change (IPCC). Yet two of the most fundamental challenges that directly threaten the ability of the IPCC to fulfill its mandate have been largely neglected so far. Firstly, the magnitude and rapid expansion of the climate change literature makes it increasingly impossible for the IPCC to conduct comprehensive and transparent assessments without major innovations in assessment practices and tools. Secondly, the structure, organization and scientific practices across the social sciences and humanities prohibit systematic learning on climate change solutions and increasingly limit the policy-relevance of IPCC assessments. We highlight the need for responses along three avenues to prepare the IPCC for continued success in the future: 1) IPCC assessments must make better use of big-data methods and available computational power to assess the growing body of literature and ensure comprehensiveness; 2) systematic review practices need to be enshrined into IPCC procedures to ensure adequate focus and transparency in its assessments; 3) a synthetic research culture needs to be established in the social sciences and humanities in order to foster knowledge accumulation and learning on climate solutions in the future. As policymakers become more interested in understanding solutions, the future prospects of global environmental assessment enterprises will depend heavily on a successful transformation within the social sciences and humanities towards systematic knowledge generation. This article is part of a special issue on solution-oriented Global Environmental Assessments.     

Adaptation to climate change: the attitudes of stakeholders in the livestock industry

It is now widely accepted that climate change is happening and that future changes will impact on many aspects of society, including agriculture. To maintain food supplies, the agricultural industry must address climate change adaptation. Key to this is the attitudes of those within the industry likely to have responsibility for adapting. This study investigated stakeholder attitudes towards adaptation to climate change in the livestock industry. Findings reveal four attitudinal groups. First, there is a ‘farmer-focused group’ that has a positive attitude about the ability of livestock farmers to adapt to climate change, but that also has the opinion that they will need additional support to adapt. Second, there is an ‘incentive for enterprise, anti-GM (genetic modification) group’ with an attitudinal position stressing that the government should have a role in implementing regulations and providing finance. This group has a negative attitude towards GM technology and does not think it will be the answer to climate change. Third, there is an ‘information and education group’ whose attitude is that the provision of information is crucial for ensuring that the livestock industry adapts. Fourth, there is a ‘pro-technology group’ who have a positive attitude towards GM technology and who are therefore willing to embrace it as the route to adaptation. Three of these four groups favour soft adaptations that maintain flexibility within the system, and only the fourth is of the opinion that adaptive capacity is not an issue and that the industry is ready to implement hard adaptations.     

The role of uncertainty in climate change adaptation strategies—A Danish water management example

We propose a generic framework to characterize climate change adaptation uncertainty according to three dimensions: level, source and nature. Our framework is different, and in this respect more comprehensive, than the present UN Intergovernmental Panel on Climate Change (IPCC) approach and could be used to address concerns that the IPCC approach is oversimplified. We have studied the role of uncertainty in climate change adaptation planning using examples from four Danish water related sectors. The dominating sources of uncertainty differ greatly among issues; most uncertainties on impacts are epistemic (reducible) by nature but uncertainties on adaptation measures are complex, with ambiguity often being added to impact uncertainties. Strategies to deal with uncertainty in climate change adaptation should reflect the nature of the uncertainty sources and how they interact with risk level and decision making: (i) epistemic uncertainties can be reduced by gaining more knowledge; (ii) uncertainties related to ambiguity can be reduced by dialogue and knowledge sharing between the different stakeholders; and (iii) aleatory uncertainty is, by its nature, non-reducible. The uncertainty cascade includes many sources and their propagation through technical and socio-economic models may add substantially to prediction uncertainties, but they may also cancel each other. Thus, even large uncertainties may have small consequences for decision making, because multiple sources of information provide sufficient knowledge to justify action in climate change adaptation.     

Different accounting approaches to harvested wood products in national greenhouse gas inventories: their incentives to achievement of major policy goals

The 2006 IPCC Guidelines for National Greenhouse Gas Inventories provide four accounting approaches to harvested wood products (HWP). These differ in the way they define system boundaries. Therefore, reported national carbon emissions differ according to the accounting approach used, and the implications of each accounting approach differ for different countries. This paper investigates four IPCC accounting approaches, as well as the 1996 IPCC default approach, to determine whether they provide incentives to achievement of major policy goals related to climate, forest, trade, and waste, taking into account indirect effects of wood use change (i.e., the effects on forest carbon stocks and on carbon emissions from the use of other fuels and materials). Conclusions are as follows: (1) The analyses produced many different results from those of previous studies. These differences appear to be attributable to whether or not the indirect effects of wood use change are taken into account and the reference scenarios that are assumed; (2) The best approaches for achieving each policy goal differ, and the best approaches for particular policy goals might pose problems for other policy goals; (3) Overall, the IPCC default approach is the best accounting approach from the viewpoint of greater compatibility with, or integration across, the array of policy goals, although it does not address the issue of an increasing global carbon stock in HWP.     

A Report on the Inter-regional Conference on Adaptation to Climate Change

The IPCC Third Assessment highlighted theneed for adaptation to climate change.Keeping in view the importance ofadaptation to climate change, particularlyin developing countries, DevelopmentAlternatives organised an Inter-regionalConference on Adaptation to Climate Change,during October 18-20, 2002, just before CoP8 at New Delhi. About 120 participants frommore than 20 countries, both developed anddeveloping, participated in the conference.The conference discussed vulnerability ofnatural and human systems and communitypractices to adapt to climate change. Theconference deliberated on training andcapacity building of communities forincreasing their resilience to adapt toadverse impacts of climate change. Theparticipants also came out with a set ofrecommendations for wider dissemination tovarious stakeholders during the COP 8 beingheld at New Delhi (from 23 October to 1November). The recommendations from theconference were used in the COP 8negotiations as well as the DelhiMinisterial Declaration. The ConferenceReport will provide a guideline for thedeveloping countries for initiating work onadaptation.     

中国气候变化影响研究概况

介绍了目前我国在未来气候变化影响研究方面的概况，气候影响研究采用的方法多为政府间气候变化专业委员会（ＩＰＣＣ） 第二工作组提出的气候变化影响评价方法。未来气候变化影响研究是在大气中ＣＯ２ 浓度加倍，或气温、降水变化的情景下，进行未来农业、林业、水资源、生态环境以及海平面上升等方面的潜在影响研究，其中有模型研究、实验室研究、宏观研究和适应对策研究等。这些研究采用的未来气候情景多为ＧＣＭ 模型预测的气候情景     

Carbon accounting for forest harvesting and wood products: review and evaluation of different approaches

Under the United Nations Framework Convention on Climate Change, more than 160 countries are required to report their national greenhouse gas inventories. To help countries meet this requirement, the Intergovernmental Panel on Climate Change (IPCC) prepared guidelines for inventorying greenhouse gases. These guidelines are regularly reviewed to ensure that they are based on the best scientific knowledge. In May 1998, in Dakar, Senegal, an IPCC expert meeting reviewed and evaluated three approaches for accounting for carbon from forest harvesting and wood products. They are the atmospheric-flow, stock-change and production approaches. In the future, governments may decide to include one of the three approaches in the land-use change and forestry module of the IPCC Guidelines for National Greenhouse Gas Inventories. Here, we demonstrate how such approaches can be evaluated using technical, scientific and policy criteria. The purpose of this evaluation is to help policy-makers potentially choose an approach for the IPCC Guidelines. This paper presents the framework of the evaluation by separating the technical and policy issues of each approach, but it does not make policy recommendations. On technical and scientific grounds, a group of experts found that the three approaches gave similar results at a global level. Data availability is not a critical factor in choosing between the approaches. However, at the national level, the approaches can differ significantly, for example, in terms of their system boundaries. Depending on technical features of each approach, credits and debits for CO₂ flows or changes in carbon stock in wood products are accounted for differently among countries that produce or consume wood. This leads to differing incentives for conserving or enhancing carbon stocks in forests, the use of imported wood products and woodfuels and waste minimisation strategies. Each approach has different implications.     

中国气候变化影响研究概况

介绍了目前我国在未来气候变化影响研究方面的概况,气候影响研究采用的方法多为政府间气候变化专业委员会(IPCC)第二工作组提出的气候变化影响评价方法。未来气候变化影响研究是在大气中C0₂浓度加倍,或气温、降水变化的情景下,进行未来农业、林业、水资源、生态环境以及海平面上升等方面的潜在影响研究,其中有模型研究、实验室研究、宏观研究和适应对策研究等。这些研究采用的未来气候情景多为GCM模型预测的气候情景。      

Climate research and policy advice: scientific and cultural constructions of knowledge

The present paper is a call to cultural sciences for helping climate science to establish a sustainable practice of policy advice concerning man-made climate change.As a climate scientists engaged in communication with stakeholders and the media, mostly in Germany, the author has noticed a notable discrepancy between scientific knowledge about climate change, and the understanding in the public at large, specifically as fostered by the media and some publicly visible climate scientists. In this essay, this discrepancy is analysed to some extent and framed as the presence of two competing types of knowledge, namely a body of knowledge named “cultural construct” and another body of knowledge named “scientific construct” of man-made climate change. The relationship and the dynamics of these two knowledge claims are not well researched. In order to understand the dynamical interaction of the different knowledge claims significant efforts from cultural sciences are needed. Unfortunately, so far these disciplines do not often consider this field. Two examples of useful analyses are presented as examples.     

Climate change: linking adaptation and mitigation through agroforestry

Agriculture is the human enterprise that is most vulnerable to climate change. Tropical agriculture, particularly subsistence agriculture is particularly vulnerable, as smallholder farmers do not have adequate resources to adapt to climate change. While agroforestry may play a significant role in mitigating the atmospheric accumulation of greenhouse gases (GHG), it also has a role to play in helping smallholder farmers adapt to climate change. In this paper, we examine data on the mitigation potential of agroforestry in the humid and sub-humid tropics. We then present the scientific evidence that leads to the expectation that agroforestry also has an important role in climate change adaptation, particularly for small holder farmers. We conclude with priority research questions that need to be answered concerning the role of agroforestry in both mitigation and adaptation to climate change.     

Societal Vulnerability to Climate Change and Variability

Institutions in many wealthy industrialised countries are robust and their societies appear to be relatively well insulated against the impacts of climate variability, economic problems elsewhere and so on. However, many countries are not in this position, and there is a growing group of humanity which is not benefiting from the apparent global adaptive trends. Worst case scenarios reinforce the impact of this uneven distribution of adaptive capacity, both between and within countries. Nevertheless, at the broad global scale human societies are strongly adaptive and not threatened by climate change for many decades. At the local level the picture is quite different and the survival of some populations at their present locations is in doubt. In the absence of abatement, the longer term outlook is highly uncertain. Adaptation research needs to begin with an understanding of social and economic vulnerability. It requires a different approach to the traditional IPCC impacts assessment, as human behaviour, institutional capacity and culture are more important than biophysical impacts. This is consistent with the intellectual history of the IPCC which has gradually embraced an increasing range of disciplines.     

Overlapping consensus versus discourse in climate change policy: The case of Norway's Sovereign Wealth Fund

This paper is motivated by the mismatch between emission of greenhouse gases and effective mitigation policies. Science now calls for every tool to be considered in order for radical changes to mitigate the situation more effectively. This paper considers Norway's huge Sovereign Wealth Fund which, although withdrawing investment from firms causing severe environmental damage, does not categorize climate change as ‘severe environmental damage’. The main reason is a basis of overlapping consensus, which also hinders argumentation for this practice.Overlapping consensus is part of the broader theory “Justice as Fairness” as conceived by John Rawls. The consensus is with regard to having a socially just system. The word ‘overlapping’ refers to people having different reasons for supporting the system. However using overlapping consensus for investment-strategies represents an extension beyond its original intention, and moreover, removes mitigating climate change from the agenda. Removing the basis of overlapping consensus opens up scope for value-based discourse conceived by Habermas’ communicative action and discourse ethics. The immense severity of climate change demands value-based and substantial arguments from powerful sovereign wealth funds, to consider the acceptability of their practice.     

Accommodating consensus and diversity in environmental knowledge production: Achieving closure through typologies in IPBES

How can a diversity of perspectives be accommodated in scientific and political consensus on environmental issues? This paper adopts a science and technology studies (STS) approach to examine how the pursuit of consensus-based knowledge and diverse participation, as seemingly contradictory commitments, have been converted into practice in the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES). Through a series of negotiations, these commitments have been translated into a set of situated practices that now dominate this expert panel. Consensus has been achieved through the pursuit of closure, in which meetings of expert and administrator groups produce texts, tables and images that stabilise ostensibly collective decisions. Within this framework, diverse perspectives have been accommodated through the production of typologies, such as lists of comparable options, which allow for the coexistence and commensurability of a range of knowledges and experts. However there is a politics to typologies, which requires specific attention to how decisions are made (deliberation), who participates in them (participation), and the extent to which these participants are representative of broader knowledge and policy communities (representation). While the potential of typologies to accommodate consensus and diversity offers the hope of realising ‘unity in diversity’ for both environmental knowledge and policy, recognising the politics of their production is important for more equitable processes of environmental governance.     

Desertification,and climate change: the case for greater convergence

Poor knowledge of links between desertification and globalclimate change is limiting funding from the Global Environment Facility foranti-desertification projects and realization of synergies between theConvention to Combat Desertification (CCD) and the FrameworkConvention on Climate Change (FCCC). Greater convergence betweenresearch in the two fields could overcome these limitations, improve ourknowledge of desertification, and benefit four areas of global climate changestudies: mitigation assessment; accounting for land cover change in thecarbon budget; land surface-atmosphere interactions; and climate changeimpact forecasting. Convergence would be assisted if desertification weretreated more as a special case in dry areas of the global process of landdegradation, and stimulated by: (a) closer cooperation between the FCCCand CCD; (b) better informal networking between desertification and globalclimate change scientists, e.g. within the framework of theIntergovernmental Panel on Climate Change (IPCC). Both strategies wouldbe facilitated if the FCCC and CCD requested the IPCC to provide ascientific framework for realizing the synergies between them.     

Adaptation Options Strategies for Hazards and Vulnerability Mitigation: An International Perspective

The broad objective of this special issue of Mitigation and Adaptation Strategies for Global Change is to address some of the gaps in our knowledge and understanding of the policies, programs, and measures that might be applied to natural hazards and their impacts in an era of climate change. Given the global impacts of climate change and world-wide pattern of increasing losses from natural hazards we necessarily adopt an international perspective. The specific goals of the special issue are to: (a) encompass experiential aspects, emphasizing current practice of mitigation and its associated measures, and their results; and (b) explore primary or root causes of alarming shifts in human and economic costs of environmental extremes. Special emphasis is placed on how human activities are playing a key role in enhancing vulnerability to NTEE (nature-triggered environmental extremes), quite independently from the anthropogenic causes of climate change. The goals are also (c) to examine costs, risks, and benefits (of all kinds including social, political, ecological) of mitigation, and adjustment and adaptation measures; and (d) analyze policy implications of alternative measures. These components are expected to make significant contributions to policy considerations – formulation, implementation and evaluation. There is much uncertainty about the rate of climate change; however, the fact of increase of the atmospheric temperature in the last century is no longer a subject of scientific or policy debate. Due to such changes in the geophysical parameters, certain types of nature-triggered environmental extreme events are likely to continue to increase. How global warming will affect regional climates and pertinent variables is not well known, limiting our ability to predict consequential effects. This factor poses serious constraints against any straightforward policy decisions. Research findings of the work of this volume reaffirm that human dimensions, specifically our awareness and decision-making behavior, are powerful explanatory factors of increasing disaster losses. Disaster mitigation through addressing human, social, and physical vulnerability is one of the best means for contributing to ‘climate change adaptation plans’, and sustainable development goals. Recent lessons from various countries have depicted that the formulation of mitigation strategies cannot be exclusively top-down as it requires social, political, and cultural acceptance and sense of ownership. An interactive, participatory process, involving local communities, produces best expected outcomes concerning mitigation, preparedness, and recovery. An emerging consensus is that there is a need to move towards the ‘mission’ of the International Strategy for Disaster Reduction which aims at building disaster resilient communities by promoting increased awareness of the importance of disaster reduction as an integral component of sustainable development, with the goal of reducing human, social, economic and environmental losses due to natural hazards and related technological and environmental disasters. Sharing of best practices and lessons globally is certain to produce more efficiency and understanding in policy and decision making.     

农田土壤N2O产生的关键微生物过程及减排措施

氧化亚氮(N2O)作为一种重要的温室气体,其全球排放总量仍然在持续上升.它不仅可以产生温室效应,还可以间接破坏臭氧层,使其在全球气候变化和生态环境变化研究中备受关注.土壤生态系统是大气中N2O的最重要排放源.本文详细论述了农田土壤中反硝化作用、硝化作用、硝化微生物的反硝化作用以及硝酸盐异化还原成铵作用等过程产生N2O的微生物学机制,并从土壤理化性质(土壤pH、氮素、有机质、土壤温度和湿度)和土壤生物等方面对农田土壤N2O排放的影响进行综述,在此基础上对农田土壤N2O的减排措施进行总结,并就今后农田土壤N2O排放的研究重点和方向进行了展望,为调控农田土壤温室气体排放、氮转化过程和提高氮素利用效率提供科学依据.     

Socio-economic impacts of climate change on rural United States

Directly or indirectly, positively or negatively, climate change will affect all sectors and regions of the United States. The impacts, however, will not be homogenous across regions, sectors, population groups or time. The literature specifically related to how climate change will affect rural communities, their resilience, and adaptive capacity in the United States (U.S.) is scarce. This article bridges this knowledge gap through an extensive review of the current state of knowledge to make inferences about the rural communities vulnerability to climate change based on Intergovernmental Panel on Climate Change (IPCC) scenarios. Our analysis shows that rural communities tend to be more vulnerable than their urban counterparts due to factors such as demography, occupations, earnings, literacy, poverty incidence, and dependency on government funds. Climate change impacts on rural communities differs across regions and economic sectors; some will likely benefit while others lose. Rural communities engaged in agricultural and forest related activities in the Northeast might benefit, while those in the Southwest and Southeast could face additional water stress and increased energy cost respectively. Developing adaptation and mitigation policy options geared towards reducing climatic vulnerability of rural communities is warranted. A set of regional and local studies is needed to delineate climate change impacts across rural and urban communities, and to develop appropriate policies to mitigate these impacts. Integrating research across disciplines, strengthening research-policy linkages, integrating ecosystem services while undertaking resource valuation, and expanding alternative energy sources, might also enhance coping capacity of rural communities in face of future climate change.     

Sustainability as an educational agenda

The mounting evidence about human-induced environmental change, and about its expected detrimental effects on humans and their societies ( [IPCC, 2007], [Reid et?al., 2010] and [Rockstr?m et?al., 2009]), has turned out to be exceedingly difficult to turn into political action to mitigate the change and adapt to its consequences. Economic self-interest creates friction between nation-states, within regional alliances like the EU, and across the divide between the developing and developed world. A significant factor is a vocal and well-funded group of climate skeptics, who question the credibility of mainstream earth system science, overemphasize the disagreements within the scientific community, argue for more research before any action is warranted, and in general create doubt to justify inaction or delay (Oreskes and Conway, 2010). A further problem is that both the decision-makers and the public have a very superficial understanding of the issues, cannot intellectually handle complex problems and uncertainty, and do not always know what and whom to believe. This constitutes a challenge to the education establishment.     

西双版纳生物多样性廊道区气候变化脆弱性评价研究

以IPCC（政府间气候变化专业委员会）对生态系统气候脆弱性定义为理论基础,以西双版纳勐腊一尚勇保护区廊道为研究区域,通过建立生态系统气候脆弱性评价指标体系,对廊道从20世纪70年代到现在和未来变化做了评估,初步识别出不同历史时期研究区的生态系统对气候变化的脆弱性特征,并提出应对气候变化的对策建议。